The feasibility of integrated nuclear desalination plants has been proven with over reactor-years of experience, chiefly in Kazakhstan, India, and Japan. Large-scale deployment of nuclear desalination on a commercial basis with reactors built primarily for that purpose will depend on economic factors. See also information paper on Radioisotopes in Medicine. Many people are aware of the wide use of radiation and radioisotopes in medicine particularly for diagnosis identification and therapy treatment of various medical conditions.
In developed countries about one person in 50 uses diagnostic nuclear medicine each year, and the frequency of therapy with radioisotopes is about one-tenth of this. Diagnostic techniques in nuclear medicine use radiopharmaceuticals or radiotracers which emit gamma rays from within the body. These tracers are generally short-lived isotopes linked to chemical compounds which permit specific physiological processes to be scrutinised.
Dependent on the type of examination, radiotracers are either injected into the body, swallowed, or inhaled in gaseous form. The emissions from the radiotracers are detected by the imaging device, which provides pictures and molecular information. The superimposition of nuclear medicine images with computed tomography CT or magnetic resonance imaging MRI scans can provide comprehensive views to physicians to aid diagnosis.
An advantage of nuclear over X-ray techniques is that both bone and soft tissue can be imaged very successfully. The most widely used diagnostic radioisotope is technetiumm, with a half-life of six hours, and which gives the patient a very low radiation dose.
Such isotopes are ideal for tracing many bodily processes with the minimum of discomfort for the patient. They are widely used to indicate tumours and to study the heart, lungs, liver, kidneys, blood circulation and volume, and bone structure. Nuclear medicine is also used for therapeutic purposes. Most commonly, radioactive iodine I is used in small amounts to treat cancer and other conditions affecting the thyroid gland.
The uses of radioisotopes in therapy are comparatively few, but important. Cancerous growths are sensitive to damage by radiation, which may be external using a gamma beam from a cobalt source , or internal using a small gamma or beta radiation source. Short-range radiotherapy is known as brachytherapy, and this is becoming the main means of treatment. Many therapeutic procedures are palliative, usually to relieve pain.
A new field is targeted alpha therapy TAT , especially for the control of dispersed cancers. The short range of very energetic alpha emissions in tissue means that a large fraction of that radiative energy goes into the targeted cancer cells once a carrier, such as a monoclonal antibody, has taken the alpha-emitting radionuclide to exactly the right places. Hospitals use gamma radiation to sterilise medical products and supplies such as syringes, gloves, clothing, and instruments that would otherwise be damaged by heat sterilisation.
Many medical products today are sterilised by gamma rays from a cobalt source, a technique which generally is much cheaper and more effective than steam heat sterilisation. The disposable syringe is an example of a product sterilised by gamma rays. Because it is a 'cold' process, radiation can be used to sterilise a range of heat-sensitive items such as powders, ointments, and solutions, as well as biological preparations such as bone, nerve, skin, etc , used in tissue grafts.
The benefit to humanity of sterilisation by radiation is tremendous. It is safer and cheaper because it can be done after the item is packaged. The sterile shelf life of the item is then practically indefinite provided the package is not broken open. Apart from syringes, medical products sterilised by radiation include cotton wool, burn dressings, surgical gloves, heart valves, bandages, plastic and rubber sheets, and surgical instruments.
In addition to agricultural pest control see Agriculture section above , SIT has found important applications in the fight against disease-carrying insects.
The most recent high-profile application of SIT has been in the fight against the deadly Zika virus in Brazil and the broader Latin America and Caribbean region. Following its outbreak, impacted countries requested urgent support from the IAEA to help develop the established technique to suppress populations of disease-carrying mosquitoes.
The IAEA responded by providing expert guidance, extensive training, and by facilitating the transfer of gamma cell irradiators to Brazil. Nuclear power is particularly suitable for vessels which need to be at sea for long periods without refuelling, or for powerful submarine propulsion. The majority of the approximately ships powered by small nuclear reactors are submarines, but they range from icebreakers to aircraft carriers.
See also information paper on Nuclear-Powered Ships. Radioisotope thermal generators RTGs are used in space missions. The heat generated by the decay of a radioactive source, often plutionium, is used to generate electricity.
The latest Mars rover, Curiosity , is much bigger and uses RTGs for heat and electricity as solar panels would not be able to supply enough electricity.
See also information paper on Nuclear Reactors for Space. In the future, electricity or heat from nuclear power plants could be used to make hydrogen. Hydrogen can be used in fuel cells to power cars, or can be burned to provide heat in place of gas without producing emissions that would cause climate change.
See also information paper on Transport and the Hydrogen Economy. See also information paper on Radioisotopes in Water Resources and the Environment. Radioisotopes play an important role in detecting and analysing pollutants. Nuclear techniques have been applied to a range of pollution problems including smog formation, sulphur dioxide contamination of the atmosphere, sewage dispersal from ocean outfalls, and oil spills.
Adequate potable water is essential for life. Yet in many parts of the world fresh water has always been scarce and in others it is becoming so. Isotope hydrology techniques enable accurate tracing and measurement of the extent of underground water resources.
Such techniques provide important analytical tools in the management and conservation of existing supplies of water and in the identification of new sources.
Additionally, most nuclear reactors can operate for very long periods of time — over 60 years in many cases. A number of different materials can be used to fuel a reactor, but most commonly uranium is used. Uranium is abundant, and can be found in many places around the world, including in the oceans.
Other fuels, such as plutonium and thorium, can also be used. A single pellet contains as much energy as there is in one tonne of coal. A typical reactor requires about 27 tonnes of fresh fuel each year. In contrast, a coal power station of a similar size would require more than two-and-a-half million tonnes of coal to produce as much electricity. Like any industry, the nuclear industry generates waste. However, unlike many industries, nuclear power generates very little of it — and fully contains and manages what it does produce.
The vast majority of the waste from nuclear power plants is not very radioactive and for many decades has been responsibly managed and disposed of. The storage sites for radioactive waste have become very controversial in the United States. For years, the government planned to construct an enormous nuclear waste facility near Yucca Mountain, Nevada, for instance.
Environmental groups and local citizens protested the plan. They worried about radioactive waste leaking into the water supply and the Yucca Mountain environment, about kilometers 80 miles from the large urban area of Las Vegas, Nevada.
Although the government began investigating the site in , it stopped planning for a nuclear waste facility in Yucca Mountain in Chernobyl Critics of nuclear energy worry that the storage facilities for radioactive waste will leak, crack, or erode. Radioactive material could then contaminate the soil and groundwater near the facility. This could lead to serious health problems for the people and organisms in the area. All communities would have to be evacuate d.
This is what happened in Chernobyl, Ukraine, in A steam explosion at one of the power plants four nuclear reactors caused a fire, called a plume. This plume was highly radioactive, creating a cloud of radioactive particles that fell to the ground, called fallout. The fallout spread over the Chernobyl facility, as well as the surrounding area. The fallout drifted with the wind, and the particles entered the water cycle as rain. Radioactivity traced to Chernobyl fell as rain over Scotland and Ireland.
Most of the radioactive fallout fell in Belarus. The environmental impact of the Chernobyl disaster was immediate. For kilometers around the facility, the pine forest dried up and died. The red color of the dead pine s earned this area the nickname the Red Forest.
Fish from the nearby Pripyat River had so much radioactivity that people could no longer eat them. Cattle and horses in the area died. More than , people were relocate d after the disaster , but the number of human victim s of Chernobyl is difficult to determine. The effects of radiation poisoning only appear after many years. Cancers and other diseases can be very difficult to trace to a single source. Future of Nuclear Energy Nuclear reactors use fission, or the splitting of atoms, to produce energy.
Nuclear energy can also be produced through fusion, or joining fusing atoms together. The sun, for instance, is constantly undergoing nuclear fusion as hydrogen atoms fuse to form helium. Because all life on our planet depends on the sun, you could say that nuclear fusion makes life on Earth possible. Nuclear power plants do not have the capability to safely and reliably produce energy from nuclear fusion. It's not clear whether the process will ever be an option for producing electricity.
Nuclear engineers are researching nuclear fusion, however, because the process will likely be safe and cost-effective. Nuclear Tectonics The decay of uranium deep inside the Earth is responsible for most of the planet's geothermal energy, causing plate tectonics and continental drift. The cooling system in one of the two reactors malfunctioned, leading to an emission of radioactive fallout. No deaths or injuries were directly linked to the accident.
Also called "the country. Unstable atomic nuclei lose energy by emitting radiation and subatomic particles. The audio, illustrations, photos, and videos are credited beneath the media asset, except for promotional images, which generally link to another page that contains the media credit. The Rights Holder for media is the person or group credited.
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Any interactives on this page can only be played while you are visiting our website. You cannot download interactives. However, over time, there has been a shift in demand for cheaper and cleaner fuel options, such as the nonrenewable energy source of natural gas, and renewable options like solar power and wind energy. Each energy resource has its advantages and disadvantages.
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